This invention relates to a plug-in coupling comprising a base body, an annular sealing element, a clamping ring and an annular body which is connectable to the base body, in which a pipe end can be fixedly secured in sealing contact with the sealing element in the plug-in coupling by the clamping ring.
Published international patent application no. WO 00/75 554 A1 discloses a plug-in coupling of this type which is constructed as a double socket and comprises a base body and a holding or clamping device for ends of each of two pipes which are to be joined together, in which the ends are insertable into the plug-in coupling. The holding device has a clamping ring which has a clamping cone on the outside radially and at least one clamping rib on the inside that can be brought into engagement with the respective pipe end. Each clamping ring is surrounded on the outside by a socket which has a mating cone on the inside radially for bracing the clamping ring. The base body has an annular groove close to the front end area with a ring-shaped sealing element which is in sealing contact with the inside surface of the pipe end inserted into the socket. The front end area of the base body and the front end of the sockets are arranged at a slight distance from the annular groove. If the pipe end is not inserted coaxially with the longitudinal axis of the plug-in coupling into the annular gap between the base body but instead is inserted at a greater or lesser angle to the longitudinal axis of the plug-in coupling, there is a risk that the sealing element will be forced at least partially out of the annular groove or damaged so that the required tight connection cannot be established and/or assured with the required functional reliability.